Pew has gone beyond the usual "do you approve of Congress's performance" question to play word-association with poll respondents...and the result is not pretty. When asked to describre Congress in a word, 86% supplied one Pew deemed "negative"; 4% gave a "positive" word.
"Dysfunctional" was the top response, and "corrupt" was second. "Self-serving," "self-centered," or "selfish" came third. "Inept" was next. The list goes on. See the full litany in the posting at Pew's website.
Pew plugged these into Wordle, and got this word cloud: